From Pathfinder Adventure: Crown of the Kobold King, which isn't enabled.

Trapped Elevator

HAZARD 2

Stealth +8 (expert)

Description An oversized cauldron rigged as an elevator suddenly drops 30 feet if it's overloaded.

Disable DC 18 Thievery (trained) to lock the releasing mechanisms in place, or DC 20 Crafting to rig additional supports for the cauldron (this activity requires 10 minutes of work)

Release the Cauldron

Trigger More than one Medium or more than two Small creatures are inside the cauldron when it is activated to lower;

Effect The cauldron releases from its anchor points on the chains and drops 30 feet to area E1; any creatures within take 15 points of bludgeoning damage in the fall. A creature can attempt to Grab an Edge to avoid falling by clinging to a chain.

Reset Creatures can still fall down the shaft even after the cauldron is released, but the cauldron must be reset manually.

Pathfinder Adventure: Crown of the Kobold KingOGL